{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T21:54:40Z","timestamp":1780610080661,"version":"3.54.1"},"reference-count":40,"publisher":"Public Library of Science (PLoS)","issue":"5","license":[{"start":{"date-parts":[[2025,5,7]],"date-time":"2025-05-07T00:00:00Z","timestamp":1746576000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec024\">\n<jats:title>Background<\/jats:title>\n<jats:p>Hypertension is the predominant risk factor for cardiovascular disease morbidity and mortality, with significant healthcare utilization and expenditure. Pharmaceutical management is habitually adopted; although its long-term effectiveness remains ambiguous, and accompanying adverse effects are disquieting. Peppermint owing to its abundance of menthol and flavonoids, possesses a range of potential hypertensive benefits.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec025\">\n<jats:title>Rationale<\/jats:title>\n<jats:p>Our previous trial has shown that peppermint is able to mediate significant improvements in systolic blood pressure in healthy individuals. But there has yet to be any randomized placebo-controlled studies, examining the efficacy of peppermint supplementation in hypertensive individuals.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec026\">\n<jats:title>Objective<\/jats:title>\n<jats:p>This study proposes a placebo randomized controlled trial, exploring the effects of daily peppermint oil supplementation on outcomes pertinent to hypertensive disease in individuals with pre and stage 1 hypertension.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec027\">\n<jats:title>Methods and analyses<\/jats:title>\n<jats:p>This 20-day, parallel randomized, placebo-controlled trial will recruit 40 individuals, assigned to receive either 100\u03bcL per day of either Peppermint oil or a peppermint flavoured placebo. The primary trial outcome will be the between-group difference in systolic blood pressure from baseline to post-intervention. Secondary outcome measurements will be between-group differences in anthropometric, haematological, diastolic blood pressure\/ resting heart rate, psychological wellbeing, and sleep efficacy indices. Statistical analysis will be conducted on an intention-to-treat basis using linear mixed effects models to contrast differences in the changes from baseline to 20-days between the two trial arms.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec028\">\n<jats:title>Ethics and dissemination<\/jats:title>\n<jats:p>Ethical approval has been granted by the University of Central Lancashire (<jats:italic>HEALTH 01074<\/jats:italic>) and the study has formally been registered as a trial (<jats:italic>NCT05561543<\/jats:italic>). Dissemination of the trial findings will be through publication in a peer-reviewed journal.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec029\">\n<jats:title>Trial registration<\/jats:title>\n<jats:p>ClinicalTrials.gov <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"https:\/\/clinicaltrials.gov\/ct2\/show\/NCT05561543\" xlink:type=\"simple\">NCT05561543<\/jats:ext-link>.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec030\">\n<jats:title>Ethics<\/jats:title>\n<jats:p>HEALTH 01074.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0321986","type":"journal-article","created":{"date-parts":[[2025,5,7]],"date-time":"2025-05-07T17:28:27Z","timestamp":1746638907000},"page":"e0321986","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":2,"title":["Effects of peppermint (Mentha piperita L.) oil in cardiometabolic outcomes in participants with pre and stage 1 hypertension: 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